Tension control mechanism



Filed Nov. 2, 1945 2 Sheets-Sheet 1 MMZZET ZZ MJJQ JA y 1949- a. M.BONEBRAKE 2,475,691

TENS ION CONTROL MECHANI S M Filed Nov. 2, 1945 2 Sheets-Sheet 2 4 am IP QM J INVENTOR. 66y Mfimzeralfe mww-w Patented JulylZ, 1949 UNITED.STATES PATENT 2,475,691 @j p TENSION CONTROLMECHANI S M GayM.Bonebrake,Chicago, 111., assignor a i Wrigley Jr. Company, Chicago, 11].,a;corpora--,.. tion ofIllinois 3 pplication November 2, 1945, Seriallilog zgggy- 4 Claims, 271-23) This invention relates to tension controlmech- In this adaptation themachine includes a cupanisms, and moreparticularly to a mechanism port l0 upon which-supply rolls l2, l3 and II of adapted to provide continuous control of the tens strip materialmay be suitably mounted in l a sion of a moving web or the like. icommon plane for rotation in response totension My invention has for ageneral object the proapplied tothe strip material. 1 vision of animproved control mechanism for rege As an example ofa practical use, thematerial ulating the tension of a moving web or the like in thesupplyroll I2 may be foil while themateby effecting controlledvariations of the speed rials in the supplies" I3 and [4 are paperwalxedof a web feeding roll atone end of the portion on both sidesandcellophanarespectively. Lamiof the web in which tension is to becontrolled. nated stripmaterlalof this type is well adapted As anotherobject my invention contemplates to the wrapping of gum,confections andthe like; the* provision of l a tension control mechanism Webs l5, l6and I1 drawn from the supply rolls adapted to use with webs of frangiblematerial or l2, l3 and "II; respectively, are laminated and the like andwhich incorporates a resilient elesealedtogetherln osely juxtaposedrelationship ment adapted to soften the controlling action of by passagebetweeniclosely spaced and subst'anl the mechanism in a manner such thatbreakage or tially parallel rolls l8 and I9; bothof whicifldlls' tearingof the web due to sudden tension varlaare rotatably supported by thesupport It: wne tions is avoided. i or roll it is carried relative tothe support I0" by*a The present invention has for a. further obcoaxialand. projecting shaft anddesirably is Ject the provision of avariablespeed feed roll 20 a heater roll hea to atemperature suchthatl't drive mechanism and associated apparatus such softensthe wax ontheweb It to provide a that the feed roll speed is responsive to thetension between the laminated layers. "The heatin of of a web or thelike whichis moved by the feed the roll lflmay be accomplishedbyanysuitable roll. i a means, such as theprovision of electricalheating It is also an object of my inventionto provide elements. i l 1 lc a tension control mechanism for regulating the The roll i9is supportedby coaxial projecting feeding of a web or the like and which is capableend portion 22 which projects through a bearing of. smooth andcontinuous, variations of speed in the support HLas shoWn in Fig.- 3? Inaddi jj between predetermined maximum and minimum tion to serving as abacking roll for the heer limits and responsive to the size of a loop inthe roll l8, the roll it also serves as a driving roll or portion of theweb in which the tension control is mo ivatin he Webs to draw thematerial r In iesired. the respective'supply rolls. n is, consequently;

Other objects and advantages of the invention desirable that the roll I!is provided with a survill be apparent from the. following descriptionface c0vering'23of a material such as cork which ind the accompanyingdrawings in which similar hroughout the several figures: i Fig. 1 is afragmentary side elevational and omewhat diagrammatic view of a portionof a iachine which incorporates a preferred form of W tension controlmechanism; i

Fig. 2 is a fragmentary side sectional view with 1e section takensubstantially on a. line 22 of 18.3; i

Fig. 3 is a fragmentary top sectional view with which project fromthesupport" l0; "Likewi ie section taken substantially on a line 3 3 ofrolls 2'! and were carried bys aasaz a ig. 1 and wherein certain partsarecut away respectively, which project outwardly fro illustrate detailsof construction; and support I0. g y .7 Fig. 4 is a fragmentary top planview of a por- After passing between the output rolls 2'! N an of thestructure shown in Fig. 3. 28, the combined web may pass toother part ofAlthough there are various types of machines; complete machineto be cutfor use, or may which my tension control mechanism is well. wound as'asupplyroll oflaminated ,ma ited, the exemplary embodiment herein dis-Thespeed of. the driven output roll or rollsde r. ised depicts itsadaptation to amachine for ably is substantiallyconstant andcorrelatd'to ninating a plurality of webs ofst'rip material. the normalspeed of the driven roll is.

- ingly secured to As operation of the machine continues in the processof laminating the separate layers of the combined web, conditions ofoperation, such as the variations and the sizes of the supply rolls l2,l3 and I4, vary the driving force necessarily applied to the web by thedriven roll l9. Thus, to maintain substantially uniform' output of thecombined web and to prevent tearing or breakage of the web between thedriven roll l9 and the driven output rolls 21 and 28, means is providedwhich is responsive to the tension of the web between those driven rollsto maintain that tension at a practically uniform value by regu latingthe speed of the driven roll l9.

For driving the driven roll l9, a drive shaft 34 is rotatably supportedin coaxial alignment with the supporting end portion 22 of the drivenroll l9 by a bearing 85 at one end of a support arm 38. In the disclosedembodiment of my invention, a flanged bracket 81 is secured to thesupport In and carries a projecting stub shaft 38 to which the other endof the support arm 38 is secured by a clamping portion 99, as shown inFig. 3.

As an exemplary form of driving connection to the drive shaft 34,apulley 48 is secured to the outer end of the shaft by means such as aset'screw 42 and is driven by means such as a belt 43. A collar 44 issecured to the shaft 94 by means such as a set screw 45 on the side ofthe bearing 35 opposite the pulley 48 to determine the axial position ofthe shaft 84. v

In order that the speed of the driven roll l9 may be varied as the driveshaft 84 is rotated at a practically constant speed, a drivingconnection between the shaft 84 and the driven roll I9 is provided byvariable speed transmission in the form of a planetary mechanism 48. Theplanetary mechanism 48 includes a sun gear 41 secured to the end of theshaft 94 and a concentrically disposed internal gear 48, between whichgears are a plurality of pinions 49 which mesh with the internal and sungears and are equidistantly spaced circumferentiallyof those gears.

In order to support the internal gear 48 and provide a partial enclosurefor the planetary mechanism, flanged bearings 50 and 52 aresecured byfastening means, such as screws 58, to opposite sides of the internalgear. The flanged bearing 59 is rotatably carried 34 while the flangedbearing 52 is carried by projecting shaft portion 54 on the end of theprojecting end portion 22 ofthe driven r011 l9.

A recess 55 is provided in the central portion of the end surface of theflanged bearin 52 to accommodate an annular plate 58 which is drivtheend of the shaft portion 54. The annular plate 55 rotatably carries thepinions 49 in their circumferentially spaced positions and thus providesa driving connection between the planetary mechanism and the driven rolll9.

It may be readily understood, by consideration of the describedstructure of the planetary mechanism 48, that when the internal gear 48is free to rotate, there will be no rotary motion transmitted throughthe planetary mechanism to the driven roll l9 since the pinions willtransmit the rotary motion of the sun gear 41 to the freerunning'internal gear. However, when the motion of the internal gear 48is impeded to a predetermined extent, the pinions 49 will necessarilytravel around the sun gear 41 and thereby transmit rotary motion to thedriven roll. The rate of rotation of the driven roll l9 will deby thedrive shaft pend upon the extent to which the motion of the internalgear is impeded and will be maximum when the internal gear is locked.

To accomplish the desired result of controlling the tension in the webin the present instance, the ratios of the gears of the planetarymechanism are preferably so related to the diameter of. the driven roll19 that when the internal gear is locked, the web will be driven at arate materially in excess of the rate of motion imparted to'the web bythe driven rolls 21 and 28. Under these circumstances, normal tensionwill be maintained in the combined web 24 between the driven roll 19 andthe driven rolls 21 and 28 when there is some rotary motion of theinternal gear 48.

In order to effect the desired control of the operation of the planetarymechanism 48 in response to the tension of the combined web 24, I haveprovided a frictional control mechanism which includes a brake band 51adapted to coact with a brake drum 58 which is secured to the outersurface of the internal gear 48. One end of the brake band 51 isadiustably secured to a bracket 59 on the support III by a clamp 88having thereon a screw 82 which is threaded into a nut 83, said nutbeing rotatably secured to the bracket 59. The other end of the brakeband i 51 is secured to one end of a lever 84 by means such as a clamp85. a

As illustrated in Figs. 2 and'3, the lever 84 is rotatably supported onthe projecting shaft 88 between one side of the bracket 81-and aloeating collar 88 which is secured to the shaft. The other end of thelever 84 ismovably connected through a motion transmitting linkage 81 toa brake control arm 88, which brake control arm is supported at one endfor swinging movement by a shaft 89 projecting from the support Ill.

In the disclosed embodiment the linkage 81 includes an adjustableelement comprising a rod 18 having its ends threaded into connectors 12and 18, which connectors are rotatably connected to the end of anangularly projecting arm 14 of a support bracket 15 and to the end ofthe lever. 84 opposite the brake band, respectively. A spring 18 havingone end anchored to the support l8 and its other end secured to aprojecting arm 11 on the bracket 15 biases the brake mechanism to aposition such that the brake band is released from the drum.

Downward swinging movement of the arm 88 in a clockwise direction, asviewed in Fig. 1, actuates the linkage 81 and lever 84 to tighten thebrake band about the drum 58 so that frictional engagement is affectedto control the rate of movement of the internal gear and thus to controlthe rate of rotation of the driven roll l8. In Order to utilize thiscontrolling action of the variable speed transmission to effect controlof the tension of the web between the driven roll l9 and the drivenrolls 21 and 28, the arm 88 has a bracket 18 secured to its swinging endfor rotatably supporting a movable roll 19.

Desirably, the normal position of the roll 18 is displaced to one sideof the idler rolls 25 and 28 so that in passing between the idler rollsand over the movable roll, a variable loop is formed in the combined web24. The biasing force of the spring 18 acts in opposition to the tensionof the web against the roll 19 to determine the position of that rolland thereby to determine the operation of the planetary mechanism 48.

The provision of a sizable loop in the com bined web 2! between idlerrolls 2! and 26 where the web passes over the movable roll 19establishes a variable section in the'course of the web and preventsvariations in tension from causing slippage or tearing the web.

As an additional factor, promoting smooth operation of the controlmechanism and easing the variations of the control mechanism in responseto sudden variations of web tension, I preferably make the arm 68 ofresilient material having characteristics such that it will flex inresponse to variations of web tension and thereby help to absorb shockor sudden changes but will not flex desired controlling forces againstthe biasing force of the spring 16 and to apply braking force to thebrake band 51.

While I have'illustrated a preferred embodiment of 'my invention, manymodifications may be made without departing from the spirit of theinvention, and I do not Wish to be limited to the precise details ofconstruction set forth, but desire to avail myself of all changes withinthe scope of the appended claims.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent of the United States, is:

1. In a tension control mechanism for regulating the tension of aflexible web or the like in a machine including support means rotatablycarrying thereon driven rolls in separated relationship and a pair ofidler rollsbetween the driven which rolls the web passes, thecombination comprising a planetary mechanism for driving one of saiddriven rolls, said planetary mechanism including concentrically disposedinternal and sun gears and a plurality of intermediate pinions meshingwith the internal and sun gears, driving means connected to the sungear, a plate connected to the last mentioned roll and rotatablycarrying said pinions, a brake drum secured to the internal gear, abrake band surrounding a portion of said brake drum, means adjustablyanchoring one end of the brake band, a rotatably supported lever havingthe other end ing an idler roll rotatably mounted thereon at a positionnormally at one side of the pair of idler rolls so as normally to effectthe formation of a loop, in the web passin around the last mentionedidler roll intermediate said pair of idler rolls, said flexible armbeing connected to the other end of said lever, means biasing saidflex,- ible arm in a direction away from said pair of idlerrolls andsuch that the brake band is separated from the drum, whereby increasedtension in the web moves the flexible arm against the force of brakeband against the drum.

2. In a tension control mechanism for regulatng the tension of aflexible web or the like in a nachine including support means rotatablycarsaid biasing means and tightens said,

the concentric gears, means for drivlngly conmeeting said pinions tosaid one of the driven rolls,

4. In a tension control mechanism for regulating'the tension of aflexible web during movement of the web in one direction in a machineincluding support means tatably supported lever having the other end ofthe brake band secured to one end thereof, a flexible arm supported atone end thereof for swinging movement toward and from said pair of idlerrolls and having an idler roll rotatably 1 from said pair at idler rollsand such that the brake band is retracted from the drum, wherebyincreased tension in the web moves the flexible Number arm against theforce of said biasing means and 449,446 tightens said brake hand againstthe drum toin- 5 889,769 crease the speed of said first driven roll.1,054,367 1,185,320 GAY M. BONEBRAKE. 1,404,081 a 1,455,916 REFERENCESCITED. m 1,763,594 2,043,354 The following references are of record inthe 2,267.10,

file of this patent:

. 8 UNITED STATES PATENTS Name Hunter Mar. 31, 1891 Didier ..'June 2,1908 mass Mar; 4, 1913 Holmes May 30, 1916 Auvil Jan. 1'1, 1922 StevensMay 22, 1923 Nelson June 10, 1930 Mallina June 9, 1936 Juiliard Dec. 23,1941

